This invention relates generally to enhanced adsorbent particles, particularly particles that have been adsorbent enhanced by contacting with acid. This invention also relates generally to an adsorbent and/or catalyst particle that has improved adsorbent properties and/or improved or newly existing catalytic properties by the use of the particle in combination with a particular binder to produce a particle/binder system. The binder can either cross-link to the particle, cross-link to itself and envelope the particle or both. This invention also relates to a binder/adsorbent and/or catalyst system that can be used as an anchored catalyst system.
Oxides of metals and certain non-metals are known to be useful for removing constituents from a gas or liquid stream by adsorbent mechanisms. For example, the use of activated alumina is considered to be an economical method for treating water for the removal of a variety of pollutants, gasses, and some liquids. Its highly porous structure allows for preferential adsorptive capacity for-moisture and contaminants contained in gasses and some liquids. It is useful as a desiccant for gasses and vapors in the petroleum industry, and has also been used as a catalyst or catalyst-carrier, in chromatography and in water purification. Removal of contaminants such as phosphates by activated alumina are known in the art. See, for example, Yee, W., xe2x80x9cSelective Removal of Mixed Phosphates by Activated Alumina,xe2x80x9d J. Amer. Waterworks Assoc., Vol. 58, pp. 239-247 (1966).
U.S. Pat. No. 4,795,735 to Liu et al. discloses an activated carbon/alumina composite and a process for producing the composite. The composite is prepared by blending powders of each of the activated carbon and activated alumina constituents. After the blend is thoroughly mixed, an aqueous solution is added to permit the activated alumina to rehydratably bond to the carbon particles. The amount of water added does not exceed that which prevents the mix from being extruded or agglomerated. After the water is added, the mix is subjected to a shaping or a forming process using extrusion, agglomeration, or pelletization to form a green body. The green body is then heated to a temperature of 25-100xc2x0 C. or higher. The composite may be strengthened by peptizing by adding nitric acid to the mixture. It is disclosed that the alumina can serve as the binder as well as the absorbent. This patent does not use a calcined alumina. Liu et al discloses an amorphous alumina trihydrate powder, such as CP2 obtained from Alcoa and an amorphous alumina trihydrate powder such as CP-1 or CP-7, which are recited in U.S. Pat. No. 4,579,839, incorporated by reference in Liu et al. Liu et al.""s use of the term active refers to the surface water being dried and does not refer to a calcined particle. Liu et al. uses acid to strengthen the particle and not to enhance its adsorbent properties. Liu et al. uses an alumina precursor, which is an absorbent and not an adsorbent.
U.S. Pat. No. 3,360,134 to Pullen discloses a composition having adsorption and catalytic properties. Example 2 discloses an alumina hydrate formed by partially dehydrating alpha-alumina trihydrate in a rotary dryer by counter-current flow with a heated gas and an inlet temperature of about 1200xc2x0 F. and an outlet temperature of about 300xc2x0 F. The resulting product was washed with 5% sulfuric acid, rinsed with water and dried to about 2% free water content. Solid sucrose was mixed with the hydrate and the mixture heated. Example 4 discloses that the procedure of Example 2 was repeated except that calcined alumina was used. The product was unsuitable when calcined alumina was used. Thus, the acid washed product of Example 2 was not a calcined alumina.
U.S. Pat. No. 4,051,072 to Bedford et al. discloses a ceramic alumina that can be treated with very dilute acid to neutralize the free alkaline metal, principally Na2O, to enable impregnation with catalytic material to a controlled depth of from at least 90 to about 250 microns. This patent does not use a crystallized aluminum oxide that has been calcined in accordance with the instant invention. This patent calcines the particle at a temperature of from about 1700xc2x0 F. to about 1860xc2x0 F. (927xc2x0 C. to 1016xc2x0 C.) to form a ceramic material, specifically what is referred to herein as an alpha alumina.
U.S. Pat. No. 5,242,879 to Abe et al. discloses that activated carbon materials, which have been subjected to carbonization and activation treatments, and then further subjected to an acid treatment and a heat treatment, have a high catalytic activity and are suitable as catalysts for the decomposition of hydrogen peroxide, hydrazines or other water pollutants such as organic acids, quaternary ammonium-salts, and sulfur-containing compounds. Acid is used to remove impurities and not to enhance the adsorbent features. This patent also does not utilize a particle of the instant invention.
Adsorbent particles of the prior art have not achieved the ability to remove particular contaminants from a liquid or gas stream, such as, for example, a waste stream or drinking water, to acceptably low levels. Additionally, the adsorbent particles of the prior art have not been able to bind tightly to particular contaminants so that the adsorbent particle/contaminant composition can be safely disposed of in a landfill. Thus, there has been a need in the art for adsorbents that have improved ability to adsorb particular materials, particularly contaminants from a gas or liquid stream, to thereby purify the stream. There has been a need in the art for the adsorbent particles to tightly bind to the adsorbed contaminant. Applicants have discovered that acid enhanced particle solves the above problems in the art.
U.S. Pat. No. 5,422,323 to Banerjee el al. discloses the preparation of a pumpable refractory insulator composition. The composition consists of the combination of a wet component of colloidal silica (40%) in water, and a dry component consisting of standard refractory material. Examples of refractory material include clay, kaolinite, mullite, alumina and alumina silicates. The resulting insulating composition was cast into shape, dried and baked to form an insulating layer.
Japanese Patent No. 63264125 to Fumikazu et al. discloses the preparation of dry dehumidifying materials. Moisture is removed from room air or gas as it passes through a dehumidifying rotor of zeolite (70% by weight) and an inorganic binder (2-30% by weight). The inorganic binder includes colloidal silica, colloidal alumina, silicates, aluminates and bentonite. Wet air was passed through the dehumidifying rotor, and the amount of dried air was assessed.
Japanese Patent No. 60141680 to Kanbe el al. discloses the preparation of a refractory lining repair material. The material was prepared by adding a solution of phosphoric acid with ultra fine silica powder to a-mixture of refractory clay and refractory aggregates composed of grog, alumina, silica, zircon and pyrophyllite. The refractory material has improved bonding strength and minute structure, and are useful for molten metal vessels such as ladles, tundishes, and electric furnaces.
Adsorbent particles of the prior art have not achieved the ability to remove particular contaminants from a liquid or gas stream, such as, for example, a waste stream or drinking water, to acceptably low levels. Additionally, the adsorbent particles of the prior art have not been able to bind tightly to particular contaminants so that the adsorbent particle/contaminant composition can be safely disposed of in a landfill. Thus, there has been a need in the art for adsorbents that have improved ability to adsorb particular materials, particularly contaminants from a gas or liquid stream, to thereby purify the stream. There has been a need in the art for the adsorbent particles to tightly bind to the adsorbed contaminant. Also, there has been a need in the art for catalysts that have the ability or that have an improved ability to catalyze the reaction of contaminants into non-contaminant by-products.
Typically in the art, binders block active sites on the adsorbent and catalyst particles, thereby reducing the efficiency of such particles. Therefore, there is a need in the art for a binder system that binds adsorbent and/or catalytic particles together without reducing the performance of the particles.
Applicants have discovered that by using a special binder for adsorbent and/or catalytic particles, improved or new adsorbent and/or catalytic properties can be achieved due to the synergy between the binder and adsorbent and/or catalyst particle.
None of the above-cited documents discloses the compositions or processes such as those described and claimed herein.
In accordance with the purpose(s) of this invention, as embodied and broadly described herein, this invention, in one-aspect, relates to a process for producing-an enhanced adsorbent particle comprising contacting a non-amorphous, non-ceramic, crystalline, porous, calcined, aluminum oxide particle that was produced by calcining at a particle temperature of from 300xc2x0 C. to 700xc2x0 C., with an acid for a sufficient time to increase the adsorbent properties of the particle.
The invention further provides a process for producing an enhanced adsorbent particle comprising contacting a non-ceramic, porous, oxide adsorbent particle with an acid for a sufficient time to increase the adsorbent properties of the particle.
In yet another aspect, the invention provides for particles made by the process of the instant invention.
In yet another aspect, the invention provides for a process for reducing or eliminating the amount of contaminants in a stream comprising contacting the particle of the invention with the stream for a sufficient time to reduce or eliminate the contamination from the stream.
In still yet another aspect, the invention provides a composition comprising the particles of the invention.
In another aspect, the invention relates to a method for producing an adsorbent and/or catalyst and binder system comprising
i) mixing components comprising
a) a binder comprising a colloidal metal oxide or colloidal metalloid oxide,
b) an oxide adsorbent and/or catalyst particle, and
c) an acid,
ii) removing a sufficient amount of water from the mixture to cross-link components a and b to form an adsorbent and/or catalyst and binder system.
In another aspect, the invention provides for an adsorbent and/or catalyst system made by the processes of the invention.
In one aspect, the invention provides an adsorbent and/or catalyst and binder system comprising a binder that has been cross-linked with at least one type of oxide adsorbent and/or catalyst particle.
In yet another aspect, the invention provides a method for reducing or eliminating the amount of a contaminant from a liquid or gas stream comprising contacting the adsorbent and/or catalyst binder system with the contaminant in the stream for a sufficient time to reduce or eliminate the amount of contaminant from the stream.
In yet another aspect, the invention provides a method for catalyzing the degradation of an organic compound comprising contacting the organic compound with the adsorbent and/or catalyst system for a sufficient time to catalyze the degradation of an organic compound.
In yet another aspect, the invention provides a method for reducing or eliminating the amount of a contaminant from a gas stream by catalysis comprising contacting the adsorbent and/or catalyst binder system with a gas stream containing a contaminant comprising an oxide of nitrogen, an oxide of sulfur, carbon monoxide, hydrogen sulfide, or mixtures thereof for a sufficient time to reduce or eliminate the contaminant amount.
In yet another aspect, the invention provides a method for producing an adsorbent and/or catalyst and binder system comprising
i) mixing components comprising
a) a binder comprising a colloidal metal oxide or colloidal metalloid oxide,
b) a first adsorbent and/or catalyst particle that does not cross-link with the binder, and
c) an acid,
ii) removing a sufficient amount of water from the mixture to cross-link component a to itself thereby entrapping and holding component b within the cross-linked binder, to form an adsorbent and/or catalyst and binder system.
In another aspect the invention relates to a composition for binding adsorbent and/or catalytic particles to produce an agglomerated particle comprising (a) a colloidal metal oxide or colloidal metalloid oxide and (b) an acid.
In another aspect the invention relates to a kit for binding adsorbent and/or catalytic particles to produce an agglomerated particle comprising (a) a colloidal metal oxide or colloidal metalloid oxide and (b) an acid.
In yet another aspect, the invention provides a method for binding adsorbent and/or catalytic particles, comprising the steps of:
(a) mixing colloidal alumina or colloidal silica with the particles and an acid;
(b) agitating the mixture to homogeneity; and
(c) heating the mixture for a sufficient time to cause cross4inking of the aluminum oxide in the mixture.
In still yet another aspect, the invention relates to an adsorbent and/or catalyst and binder system, comprising:
(a) a pendant ligand substituted or unsubstituted binder, and
(b) a pendant ligand substituted or unsubstituted oxide adsorbent and/or oxide catalyst particle, wherein at least one of components (a) and (b) is pendant ligand substituted, and wherein component (a) is cross-linked with component (b).
In another aspect, the invention relates to a method of using the above system as a catalyst support system comprising binding the above system with a second catalyst particle.
In still yet another aspect, the invention relates to an anchored adsorbent and/or catalyst and binder system, comprising:
(a) a pendant ligand substituted or unsubstituted binder, and
(b) a pendant ligand substituted or unsubstituted oxide adsorbent and/or oxide catalyst particle, and
(c) a metal complex, wherein at least one of components (a) and (b) is pendant ligand substituted, wherein component (a) is cross-inked with component (b), and wherein the metal complex (c) is bound to component (a) and/or (b).
In still yet another aspect, the invention relates to a method for producing a pendant ligand substituted adsorbent and/or catalyst system, comprising:
(i) mixing components, comprising:
(a) a pendant ligand substituted or unsubstituted binder comprising a colloidal metal oxide or a colloidal metalloid oxide,
(b) a pendant ligand substituted or unsubstituted oxide adsorbent and/or oxide catalyst particle, and
(c) an acid, wherein at least one of components (a) and (b) is pendant ligand substituted, and
(ii) removing a sufficient amount of water from the mixture to cross-link components (a) and (b) to form a pendant ligand substituted adsorbent and/or catalyst and binder system.
This method can further comprise (iii) binding a metal complex onto the resulting system of step (ii) to form the anchored catalyst system.
In still yet another aspect, the invention relates to a method for producing an adsorbent and/or catalyst and binder system comprising
(i) mixing components comprising
(a) a binder comprising a colloidal metal oxide or colloidal metalloid oxide,
(b) an oxide adsorbent and/or catalyst particle, and
(c) an acid,
(ii) removing a sufficient amount of water from the mixture to cross-link components a and b to form an adsorbent and/or catalyst and binder system, and
iii) reacting the resultant oxide adsorbent and/or oxide catalyst particle and the binder system of step (ii) with a hydroxyl-reactive compound to form a pendant ligand substituted oxide adsorbent and/or oxide catalyst and binder system.
In another aspect, the invention relates to the above method further comprising after step (iii) binding a metal complex onto the resulting system of step (iii) to form an anchored catalyst system.
In another aspect, the invention relates to an anchored adsorbent and/or catalyst and binder system, comprising:
(a) a binder, and
(b) an oxide adsorbent and/or oxide catalyst particle, and
(c) a metal complex, wherein component (a) is cross-linked with component (b), and wherein the metal complex (c) is bound directly to component (a) and/or (b).
In still yet another aspect, the invention relates to a method for producing an anchored adsorbent and/or catalyst system, comprising:
(i) mixing components, comprising:
(a) a binder comprising a colloidal metal oxide or a colloidal metalloid oxide,
(b) an oxide adsorbent and/or oxide catalyst particle, and
(c) an acid,
(ii) removing a sufficient amount of water from the mixture to cross-link components (a) and (b) to form an adsorbent and/or catalyst and binder system, and
(iii) binding a metal complex directly onto the resulting system of step (ii) to form the anchored catalyst system.
In another aspect, the invention relates to a method of encapsulating a contaminant within an adsorbent particle comprising heating the particle of the invention that has adsorbed a contaminant to a temperature sufficient to close the pores of the particle to thereby encapsulate the contaminant within the particle.
In another aspect, the invention relates to a method for regenerating the adsorbent particle that has adsorbed a contaminant.
Additional advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.